This project will determine whether pancreatic adenocarcinoma (PAC) cells harvested from a patient with cystic fibrosis (CF) can serve as a model system for physiological, biochemical and genetic studies of the CF defect. Cells of three morphologies are apparent in outgrowths of tumor explants in vitro, and primary tumors have been established in athymic mice. Patch-clamp recording from cells with epithelial morphology show the Cl-selective channel characteristic of secretory epithelia whose regulation is defective in CF. Other available PAC cell lines will be obtained and studied in parallel to identify controls for the CFPAC cell lines. A variety of studies will be performed: (i) we will define the optimal culture conditions for these cells with respect to media, serum, supplements and substrates; (ii) we will screen their transport properties with a recently developed anion flux assay and perform detailed transport studies in the interesting cell lines using single-channel and transepithelial measurements; (iii) we will assess the detailed morphology of interesting lines and examine their expression of epithelial and PAC antigenic markers; and (iv) we will determine the structural integrity of chromosome 7 in these cells using karyotype and restriction fragment length polymorphism (RFLP) analyses. These studies will bring our knowledge of these cells to the level that has been achieved using primary cultures of airway cells and establish their utility as a unique tumor cell model for cystic fibrosis.